Sisley was a son of well-to-do English parents who planned that he would have a career in business. His father, a merchant trading with the U.S. sent Sisley to London, where he began to draw, from 1857 until 1862. In 1862 he returned to Paris and studied at the Atelier Gleyre with Monet, Renoir and Bazille. In 1863 he made early attempts at plein-air painting with his friends at Chailly-en-Biere, near Barbizon. He worked with Renoir, Monet and Pissarro in 1865 at Marlotte, and with Renoir on a boat on the Seine. He exhibited for the first time in 1866 and married Marie Lescouezec the same year. The couple had two children. He called for the founding of a "Salon des Refuses" with others in 1867, after he was rejected by the Salon. He painted at Honfleur at that time.

In 1870, he showed some of his Impressionist works at the Salon. When he stayed at Voisins-Louveciennes during the Commune in 1871 Durand-Ruel exhibited one of his pictures in London, and began to buy regularly from him the following year. During this period, he painted impressionist river landscapes and village scenes (many in the snow) at Argenteuil, Bougival and Louveciennes. While he lived at Mary-le-Roi, in 1875, he was involved in a failed auction sale of pictures at the Hotel Drouot with Renoir and others. He exhibited a few times at the Impressionist Exhibitions, and at Durand-Ruel's in London, Boston, Rotterdam, Berlin and New York during the years 1876-1889. He moved to Sevres in 1877, supported by the hotelier Murer and the Publisher Charpentier. Sisley lived in dire poverty in 1878 and 1879, since only a few purchases were arranged by Duret. He lived at Veneux-Nadon with Monet, settled in Moret-sur-Loing, at Sablons, and then moved for the last time to Moret in 1889. He remained an exponent of pure Impressionist landscape painting to the end. He was elected a member of the "Nationale" in 1890, and subsequently exhibited in their Salon. In the years of 1893/94, he painted some of his best picture series (an idea borrowed from Monet). He held a large retrospective at G. Petit's in 1897, but met with little success with the critics and collectors. Sisley was seriously ill with cancer in 1898 and he had no money to apply for French citizenship. He died in 1899 at Moret-sur-Loing. At the posthumous auction of his work in 1899, the prices for his pictures began to rise appreciably. In 1911 a memorial was built for him at Moret, the first such for an Impressionist.